Encapsulated solder TSV insertion interconnect

ABSTRACT

A method of coupling a first semiconductor device to a second semiconductor device can include encapsulating solder balls on a first surface of a first substrate of the first semiconductor device with an encapsulant material. In some embodiments, the method includes removing a portion of the encapsulant material and a portion the solder balls to form a mating surface. The method can include reflowing the solder balls. In some embodiments, the method includes inserting exposed conductive pillars of the second semiconductor device into the reflowed solder balls.

TECHNICAL FIELD

The embodiments described herein relate to semiconductor devices,semiconductor device assemblies, and methods of providing suchsemiconductor devices and semiconductor device assemblies.

BACKGROUND

Semiconductor device assemblies, including, but not limited to, memorychips, microprocessor chips, imager chips, and the like, typicallyinclude a semiconductor device having a die mounted on a substrate.Semiconductor devices may include various functional features, such asmemory cells, processor circuits, and imager devices, and bond pads thatare electrically connected to the functional features. The semiconductordevice assembly may include several semiconductor devices stacked uponand electrically connected to one another by individual interconnectsbetween adjacent devices within a package.

Various methods and/or techniques may be employed to electricallyinterconnect adjacent semiconductor devices and/or substrates in asemiconductor device assembly. For example, individual interconnects maybe formed by reflowing tin-silver (SnAg), also known as solder, toconnect a pillar to a pad. Typically, the pillar may extend down from abottom surface of a semiconductor device towards a pad formed at the topsurface of another semiconductor device or substrate. A grid array ofsolder balls may be used to connect a semiconductor device assembly to acircuit board or other external device.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a cross-sectional schematic of an embodiment of asemiconductor device assembly.

FIG. 2 is a cross-sectional schematic of an embodiment of asemiconductor device assembly.

FIG. 3 is a cross-sectional schematic of an embodiment of asemiconductor device assembly.

FIG. 4 is a cross-sectional schematic of an embodiment of asemiconductor device assembly.

FIG. 5 is a partial cross-section schematic of an embodiment of asemiconductor device.

FIG. 6 is a bottom view schematic of an embodiment of a semiconductordevice.

FIG. 7A is a cross-sectional schematic of an embodiment of asemiconductor device.

FIG. 7B is a cross-sectional schematic of an embodiment of asemiconductor device.

FIG. 7C is a cross-sectional schematic of an embodiment of asemiconductor device.

FIG. 7D is a cross-sectional schematic of an embodiment of asemiconductor device.

FIG. 7E is a cross-sectional schematic of an embodiment of asemiconductor device.

FIG. 8 is a cross-sectional schematic of an embodiment of asemiconductor device.

FIG. 9 is a flow chart of one embodiment of a method of making asemiconductor device assembly.

FIG. 10A is an illustration of semiconductor devices having connectorarrays of different densities.

FIGS. 10B-10C are schematic cross-sectional views of density-conversionconnectors connected to die stacks.

FIGS. 11A-11F show various aspects of a method of manufacturing asemiconductor device assembly with exposed TSVs connected to solderballs embedded in an encapsulant.

FIGS. 12A-12F are schematic cross-sectional views of embodiments ofsemiconductor device assemblies manufactured using one or more aspectsof the methods illustrated in FIGS. 11A-11F.

FIG. 13 is a schematic view showing a system that includes asemiconductor device assembly configured in accordance with anembodiment of the present technology.

The present technology is described below with respect to specificembodiments that are shown by way of example in the drawings, but thepresent technology has various modifications and alternate forms. Thefollowing disclosure is accordingly not intended to be limited to theparticular examples disclosed. Rather, the intention is to cover allmodifications, equivalents and alternatives falling within the scope ofthe disclosure as defined by the appended claims.

DETAILED DESCRIPTION

Numerous specific details are described herein to provide a thorough andenabling description for embodiments of the present disclosure. One ofordinary skill in the art will recognize that the disclosure can bepracticed without one or more of the specific details. Well-knownstructures and/or operations often associated with semiconductor devicesmay not be shown and/or may not be described in detail to avoidobscuring other aspects of the disclosure. In general, various otherdevices, systems, and/or methods in addition to those specificembodiments disclosed herein may be within the scope of the presentdisclosure.

The term “semiconductor device assembly” can refer to an assembly of oneor more semiconductor devices, semiconductor device packages, and/orsubstrates, which may include interposers, supports, and/or othersuitable substrates. A semiconductor device assembly may be manufacturedas, but is not limited to, a discrete package form, strip or matrixform, and/or wafer panel form. The term “semiconductor device” generallyrefers to a solid-state device that includes semiconductor material. Asemiconductor device can include, for example, a semiconductorsubstrate, wafer, panel, or a single die from a wafer or substrate. Asemiconductor device may refer herein to a semiconductor die, butsemiconductor devices are not limited to semiconductor dies.

The term “semiconductor device package” can refer to an arrangement withone or more semiconductor devices incorporated into a common package. Asemiconductor package can include a housing or casing that partially orcompletely encapsulates at least one semiconductor device. Asemiconductor package can also include a substrate that carries one ormore semiconductor devices. The substrate may be attached to orotherwise be incorporated within the housing or casing.

As used herein, the terms “vertical,” “lateral,” “upper,” and “lower”can refer to relative directions or positions of features in thesemiconductor devices and/or semiconductor device assemblies shown inthe Figures. For example, “upper” or “uppermost” can refer to a featurecloser to the top of a page than another feature. These terms, however,should be construed to include semiconductor devices and/orsemiconductor device assemblies having other orientations, such asinverted or inclined orientations where top/bottom, over/under,above/below, up/down, and left/right can be interchanged depending onthe orientation.

Some semiconductor devices may not be connected in a stackedarrangement, or some semiconductor device assemblies may not beconnected to a support substrate, using conventional grid arrays ofsolder balls. For example, it is difficult to connect devices withdifferent densities of connectors using a grid array of solder balls.This difficulty can be amplified in assemblies connecting semiconductordevices with high-density exposed via pillars with standard (e.g., JEDECstandard) contact arrangements. Also, it is desirable to testsemiconductor device assemblies while they are connected to an externaldevice.

Various embodiments of this disclosure are directed to semiconductordevices, semiconductor device assemblies, and methods of making and/oroperating semiconductor devices and/or semiconductor device assembliesthat provide connections for more types of stacked die arrangements andenable testing while connected to an external device. More specifically,the embodiments of the present technology relate to methods and systemsfor electrically connecting a first semiconductor device having exposedpillars (e.g., exposed TSVs) to a second semiconductor device having asubstrate, die, and/or other components. In this regard, severalembodiments of the present technology are directed to methods ofmanufacturing semiconductor device assemblies. These methods caninclude, for example encapsulating solder balls on a first surface of afirst substrate of the first semiconductor device with an encapsulantmaterial. In some embodiments, the methods include removing a portion ofthe encapsulant material and a portion the solder balls to form a matingsurface. The methods can include reflowing the solder balls andinserting exposed conductive pillars of the second semiconductor deviceinto the reflowed solder balls. Several embodiments of the methods ofmanufacturing include encapsulating solder balls on the first set ofcontacts of a first substrate with a first encapsulant and removing aportion of the first encapsulant to expose a portion of the solder ballson the first set of contacts. These methods can include reflowing thesolder balls on the first set of contacts after removing the portion ofthe first encapsulant and inserting a first set of exposed conductivepillars extending from a second substrate into the reflowed solder ballson the first set of contacts. Still other embodiment of the methods ofmanufacturing can include providing a first substrate having a first setof solder balls encapsulated in a first encapsulant on a first side ofthe first substrate. These methods can include removing a portion of thefirst encapsulant to partially expose the first set of solder balls. Insome embodiments, these methods include increasing the temperature ofthe exposed first set of solder balls to a reflow temperature andinserting a first set of exposed conductive pillars into the reflowedfirst set of solder balls.

FIG. 1 shows an embodiment of a semiconductor device assembly 100A(“assembly 100A”) that includes a first substrate 110A and a secondsubstrate 120A over the first substrate 110A. The first substrate 110Aincludes a first surface 111 (e.g., a top surface) and a second surface112 (e.g., a bottom surface) opposite the first surface 111. The firstsubstrate 110A includes at least one pad 113 at the first surface 111and at least one pad 116 at the second surface 112. The assembly 100Acan have pillars 115 that each have an embedded portion 115A within thefirst substrate 110A and an exposed portion 115B that projects from thesecond surface 112 of the first substrate 110A. The pillars 115 can beformed by filling through-silicon vias (TSVs) in the first substrate110A with a conductive material, as discussed herein. As used herein,the term “pillar” can refer to a TSV, a through-wafer via, through via,or other conductive interconnect that is pillar-shaped and extends intoand projects out from a wafer, die, substrate, or other semiconductorstructure. The pillars 115 can be adjacent a lateral side 129 of thefirst substrate 110A, as shown in FIG. 1. The assembly 100A can alsohave interconnections 114 within the first substrate 110A and pads 116at the second surface 112. The interconnections 114 can electricallycouple the pillars 115 with one or more of the pads 113 and/orelectrically couple the pads 116 with corresponding pads 113.

The second substrate 120A can include a first surface 131 (e.g., a topsurface), a second surface 133 (e.g., a bottom surface) opposite of thefirst surface 131, and one or more pillars 125 that project from thesecond surface 133 of the second substrate 120A (e.g., toward the firstsubstrate 110A). The assembly 100A also has an interconnect 140comprising the pillar 125 of the second substrate 120A and the pad 113located at the first surface 111 of the first substrate 110A. Theinterconnect 140 electrically connects the first substrate 110A with thesecond substrate 120A. The second substrate 120A can include severalpillars 125 and the first substrate 110A can include several pads 133,and thus the assembly 100A can include several interconnects 140.

The assembly 100A can further include additional substrates, such as athird substrate 120B over the second substrate 120A, a fourth substrate120C over the third substrate 120B, a fifth substrate 120D over thefourth substrate 120C, etc. The second-fifth substrates 120A-120D can beelectrically coupled by vias 135 and interconnects 130. The vias 135 canbe through silicon vias that extend through the substrates 120A-120D,and the interconnects 130 can be conductive features between adjacentsubstrates 120A-120D. The electrical interconnects between thesubstrates 110A, 120A, 120B, 120C, 120D are shown schematically forclarity and may be varied as would be appreciated by one of ordinaryskill in the art having the benefit of this disclosure. In someembodiments, the assembly 100A can include more or fewer than fivesubstrates (e.g., at least three, at least seven, and/or at least tensubstrates). The semiconductor device assembly 100A may include thefirst substrate 110A and the second substrate 120A alone.

The interconnections 130, 140 electrically connect each of thesubstrates 110A, 120A, 120B, 120C, 120D together. The pads 116 at thesecond surface 112 of the first substrate 110A may be test padsconfigured to permit testing of the semiconductor device assembly 100A.For example, a probe may contact one of the pads 116 to test theoperational functionality of any one of the substrates 110A, 120A, 120B,120C, 120D of the semiconductor device assembly 100A. In someembodiments, one or more pads 116 (e.g., test pads) are located on boththe first surface 111 and the second surface 112 of the first substrate110A. The first substrate 110A may be a silicon substrate or othersemiconductor device, such as a logic device, or it can be a printedcircuit board or the like. The second substrate 120A, third substrate120B, fourth substrate 120C, and fifth substrate 120D may be varioussemiconductor devices. For example, one or more of the second substrate120A, third substrate 120B, fourth substrate 120C, and fifth substrate120D may be memory devices. The number, configuration, type, size,and/or location of the substrates may be varied depending on theapplication as would be appreciated by one of ordinary skill in the arthaving the benefit of this disclosure. For example, the semiconductordevice assembly 100A may comprise more or fewer substrates than shown.Likewise, the number, size, type, location, and/or configuration of thepillars, pads, and/or interconnections are shown for illustrativepurposes and may be varied depending on application as would beappreciated by one of ordinary skill in the art having the benefit ofthis disclosure.

FIG. 2 shows an embodiment of a semiconductor device assembly 100B(“assembly 100B”) that includes a first substrate 110B and second-fifthsubstrates 120A-120D. The assembly 100B has pads 116 at the firstsurface 111 of the first substrate 110B instead of the second surface112 of the first substrate 110A shown in FIG. 1. Also, the fifthsubstrate 120 may not include vias 135. Otherwise the assembly 100B isthe same as the assembly 100A and like reference numbers refer to likecomponents such that the description of the assembly 100A with respectto FIG. 1 applies to the assembly 100B shown in FIG. 2.

FIG. 3 shows an embodiment of a semiconductor device assembly 100C(“assembly 100C”) that includes a first substrate 110C and second-fifthsubstrates 120A-120D. The assembly 100C has pads 116 at the firstsurface 111 of the first substrate 110C instead of the second surface112 of the first substrate 110A shown in FIG. 1. Also, the pads 116 areon either side of the stack of substrates 120A-120D, rather than on onlyone side of the stack of substrates 120A-120D. Also, the fifth substrate120 may or may not include vias 135. Otherwise the assembly 100C is thesame as the assembly 100A and like reference numbers refer to likecomponents such that the description of the assembly 100A with respectto FIG. 1 applies to the assembly 100C shown in FIG. 3.

FIG. 4 shows an embodiment of a semiconductor device assembly 100D(“assembly 100D”) that includes a first substrate 110D and second-fifthsubstrates 120A-120D. The pillars 115 of the assembly 100D can includean exterior layer or coating 118 (described in more detail below). Theexternal layer 118 can be a protective layer that reduces the risk ofdamage to the pillars 115 (e.g., to the exposed portions 115B of thepillars, which may comprise copper and/or other soft materials) byprobes or other mechanisms used to test the semiconductor deviceassembly 100D (e.g., testing via contact between the probe and thepillars 115). The exterior layer or coating 118 may include variousmaterials that permit the probing of a pillar 115 that may be removed bysubsequent processing. For example, the exterior layer 118 may include,but is not limited to, tantalum. Also, the fifth substrate 120 may notinclude vias 135. Otherwise the assembly 100D is the same as theassembly 100A and like reference numbers refer to like components suchthat the description of the assembly 100A with respect to FIG. 1 appliesto the assembly 100D shown in FIG. 4.

FIG. 5 is a partial cross-section schematic of an embodiment of asubstrate 110. The substrate 110 includes a plurality of vias, or TSVs,109 (only one shown in FIG. 5) in the substrate 110. Various methods maybe used to form a TSV 109. For example, the TSV 109 includes an oxidelayer 119, a tantalum layer 118 on the oxide layer 119, and an innerconductive material 117 within the tantalum layer 118. The innerconductive material 117 can include a first conductive portion 117B onthe tantalum layer 118 and a second conductive portion 117A within thefirst conductive portion 117B. For example, the first conductive portion117B may be deposited via physical vapor deposition while the secondconductive portion 117A may be deposited via electrochemical deposition.The first and second conductive portions 117A, 117B may comprise copper,tungsten, poly silicon, or the like. The TSVs can also be formed usingother methods as known in the art.

A portion of the substrate 110 may be removed (e.g., ground, etched,removed using chemical-mechanical planarization, and/or ablated) toexpose a portion of the TSV 109, which results in an exposed portion115B of pillar 115. A portion of the TSV 109, also referred to as anembedded portion 115A, remains within the substrate 110. If thesubstrate 110 includes test pads 116 (shown in FIGS. 1-3), then theoxide layer 119 and tantalum layer 118 may be removed to provide anexposed conductive pillar 115B. In some embodiments, if the substrate110 does not include any test pads 116, then only the oxide layer 119may need to be removed leaving the exposed portion 115B of the pillar115, or TSV 109, to be coated with a tantalum layer 118. The tantalumlayer 118 can enable the probing of the exposed portion 115 b of thepillar 115 to test the substrate 110 while reducing or eliminating thelikelihood of damaging the conductive layers 117A, 117B of the pillar115. After the substrate 110 has been tested, the tantalum layer 118 maybe removed to potentially leave an unmarked exposed pillar 115B, whichmay be comprised of copper.

FIG. 6 is a bottom view schematic of an embodiment of a semiconductordevice 110. The bottom surface 112 of the semiconductor device 110includes a plurality of pillars 115 arranged in a high-densityrectangular array. As shown in FIG. 6, the rectangular array of pillars115 is adjacent to a side 141 of the bottom surface 112 of thesemiconductor device 110. The array is shown as a four (4) by fifteen(15) array of pillars 115 for clarity. The size of the array, shape ofthe array, and/or number of pillars 115 may be varied depending on theapplication. For example, one embodiment may include an array of eight(8) by one hundred twenty-three (123) pillars adjacent to a side of thesemiconductor device 110. The array area may be thirteen (13) mm by six(6) mm, the pad size for each pillar may be fifty-four (54) microns, andthe pad pitch may be sixty (60) microns.

FIGS. 7A-7E show aspects of forming an embodiment of a semiconductordevice 210. A first layer 212A may be deposited onto a surface of asubstrate 211, which may be a silicon substrate (see FIG. 7A), and aplurality of pads 216 (e.g., test pads) may be formed in the first layer212A. The number, size, location, and/or configuration of the pads 216may be varied. The first layer 212A is shown as a single layer forclarity in FIG. 7A. However, the first layer 212A may be comprised ofmultiple layers deposited onto the surface of the silicon substrate 211.

FIG. 7B shows at least one second layer 212B has been added to thesemiconductor device 210. The second layer 212B can be added to thefirst layer 212A. The second layer 212B can include interconnects 214,or the like, that will provide electrical connections between variouselements, such as the pillars 215 and pads 216, of the semiconductordevice 210. The second layer 212B is shown as a single layer for clarityin FIG. 7B, but can also comprise multiple layers. For example, the atleast second layer 212B may comprise multiple layers deposited onto thesurface of the silicon substrate 211 and/or onto the first layer 212A. Aplurality of TSVs, or vias, can be formed in the layers 212A, 212B andcan extend into a portion of the silicon substrate 211. The TSVs arefilled with a conductive material, such as copper, or the like, to formpillars 215. Various coatings may be applied to the TSVs prior to thedepositing of the conductive material, as discussed herein.

FIG. 7C shows at least one third layer 212C added to the semiconductordevice 210. The third layer 212C can include at least one pad 213, forelectrically connecting the semiconductor device 210 to an adjacentsemiconductor device. The third layer 212C is shown as a single layerfor clarity in FIG. 7C. However, the third layer 212C may comprisemultiple layers deposited onto one or more of the first layer(s) 212A,the second layer(s) 212B, and the surface of the silicon substrate 211.As discussed above, at least one pad 213 can be formed in the layers212C. The interconnects 214 can electrically connect the pad 213 withone or both pillars 215 and the test pads 216.

FIG. 7D shows an embodiment of a semiconductor device or substrate 210Aafter a portion of the silicon substrate 211 has been removed to exposea portion of the plurality of pillars 215 while leaving a portion of thesilicon substrate 211 on the bottom of the semiconductor device 210A.Various processes may be used to remove the portion of the siliconsubstrate 211. The silicon substrate 211 prevents probing of the pads216. Instead, the semiconductor device 210A may be tested by probing oneor more of the pillars 215. The pillars 215 can include an exteriorcoating 218, which can enable the pillars 215 to be probed whilereducing the risk of marking and/or damage to the inner conductiveportion of the pillar 215, as discussed herein. The coating 218 may bevarious, such as tantalum. The coating 218 may be removed from theexterior of the pillars 215 after desired testing of the semiconductordevice 210A, as discussed herein.

FIG. 7E shows an embodiment of a semiconductor device or substrate 210Bafter the remaining portion of the silicon substrate 211 has beenremoved from the bottom of the semiconductor device 210B to expose thetest pads 216. Various processes may be used to remove the portion ofthe silicon substrate 211. The semiconductor device 210B may be testedby the probing of one or more of the pads 216. Likewise, the pads 216may be probed to test other semiconductor devices that may beelectrically connected to the semiconductor device 210B via pad 213 atthe top surface of the semiconductor device 210B.

FIG. 8 shows an embodiment of a semiconductor device or substrate 310.The semiconductor device 310 includes a pad 313 at the top surface andpads 316 at the bottom surface. A plurality of pillars 315 extend fromthe bottom surface of the semiconductor device 310 with a portion of thepillars 315 remaining embedded within the semiconductor device 310. Asdiscussed herein, the pillars 315 are formed by filling TSVs in thesemiconductor device 310 with copper, or the like. The pillars 315 canbe adjacent to a side of the semiconductor device 310. Interconnections314 within the semiconductor device 310 can electrically connect thepillars 315 with the pad 313 at the top surface. Likewise, theinterconnections 314 within the semiconductor device 310 canelectrically connect the pads 116 at the bottom surface of thesemiconductor device 310 with the pad 113 at the top surface as well asthe pillars 315. The pillars 315 can include feet 319 located at the endof each pillar 315. The feet 319 may aid in connecting of the pillars315 to an external device.

FIG. 9 is a flow chart of one embodiment of a method 400 of making asemiconductor device assembly. The method 400 can include providing asilicon substrate having a first surface and a second surface oppositethe first surface, at step 410. The method 400 can include forming afirst layer on the first surface of the silicon substrate, at step 420.The first layer may be comprised of multiple layers deposited on thesurface of the silicon substrate as would be appreciated by one ofordinary skill in the art having the benefit of this disclosure. Atoptional step 425, the method 400 may include forming at least one testpad in the first layer, which may be multiple layers, deposited on thesurface of the substrate. The method 400 can include forming a secondlayer on the semiconductor device, at step 430. As discussed herein, thesecond layer may be comprised of multiple layers deposited on the firstlayer, or first layers, on the silicon substrate.

At step 440, the method 400 can include creating at least one TSV thatextends from the second layer, or second layers, through the firstlayer, or first layers, and into at least a portion of the siliconsubstrate. The method 400 may include forming a plurality of TSVs, whichmay be formed in an array (e.g., a rectangular array, circular array,linear array, or other shaped array). The array can be adjacent to aside of the silicon substrate. The method 400 may include forminginterconnects within the second layer, or second layers, as discussedherein, at step 446. The method 400 may include applying an oxide layerand applying a tantalum layer to the at least one TSV, at optional step445. At step 450, the method 400 can include filling the at least oneTSV, or the plurality of TSVs, with copper, or the like.

The method 400 can include forming at least a third layer on the secondlayer. The third layer can include at least one pad that is configuredto connect to a semiconductor device and forming interconnectionsbetween the at least one copper filled TSV and the at least one pad, atstep 460. The third layer may be comprised of multiple layers depositedon second layer, or second layers, as would be appreciated by one ofordinary skill in the art having the benefit of this disclosure. Themethod 400 can include removing silicon from the second or bottomsurface of the silicon substrate to expose a portion of the at least onecopper, or the like, filled TSV, or a portion of the plurality ofcopper, or the like, filled TSVs, at step 470. The method 400 mayinclude removing silicon to expose the at least one test pad, atoptional step 475. The method 400 may include removing the oxide layerfrom the exposed portion of the at least one copper, or the like, filledTSV, at optional step 480. The method 400 may include applying a probeto the tantalum layer of the exposed portion of the at least one copper,or the like, filled TSV, at optional step 485. The method 400 mayinclude removing the tantalum layer of the exposed portion of the atleast one copper, or the like, filled TSV, at optional step 490.

Semiconductor device assemblies with high-density exposed via arrays(e.g., pillar arrays), such as those described above with reference toFIGS. 1-9, often need to be connected to semiconductor device assemblieshaving lower-density connection arrays. This is particularly the casewhen the external connections are exposed portions of TSVs because TSVarrays can have higher densities than many other types of arrays. Forexample, as illustrated in FIG. 10A, it may be desirable to connect afirst semiconductor device or device assembly 500A that has ahigh-density array of pillars or exposed vias (e.g., exposed portions ofTSVs or other through-vias) 515 with a second semiconductor device 500Bhaving a lower-density array of connections 516 (e.g., a lower-densityarray of pads, solder connections, pillars, or other connectionstructure). The high-density array of pillars 515 has a smaller averagelateral distance (e.g., high-density pitch) between the pillars 515 thanthe average lateral distance (e.g., low-density pitch) between theconnections 516. The average lateral distance can be measured betweenthe center points of adjacent pillars 515 or connections 516. In someembodiments, the average lateral distance of the high-density pillars515 (e.g., the exposed TSV portions) is less than 100 microns, less than90 microns, less than 80 microns, less than 70 microns, and/or less than60 microns. In some embodiments, the footprint of the array ofconnections 516 is larger than the footprint of the array of pillars515, as measured parallel to the respective substrates through/on whichthe pillars and connections are formed. This relative difference in sizeof footprint can be present when the respective arrays of pillars andconnections 515, 516 have the same number of pillars/connections.

FIGS. 10B and 10C show a density-conversion connector 520 for connectinga first semiconductor device assembly 500A having a high-density arrayof pillars 515 to devices having lower-density arrays. Thedensity-conversion connector 520 can include a substrate 522 having afirst side 524, a second side 526 opposite the first side 524, a firstarray of pads 528 or other contacts at the first side 524, and a secondarray of pads 530 at the second side 526. In the embodiment shown inFIGS. 10B and 10C, the second array of pads 530 has a lower density thanthe first array of pads 528. For example, the density of the first arrayof pads 528 is the same as or similar to the density of the array ofpillars 515 on the semiconductor device assembly 500A, and the densityof the second array of pads 530 can be the same as or similar to thedensity of the array of connectors 516 of the second semiconductordevice 500B (FIG. 10A). Various electrical connection structures (e.g.,TSVs, interconnects, etc.) may be embedded in the substrate 522 toconnect the first array of pads 528 to the second array of pads 530.

The first semiconductor device assembly 500A can include a die stack 540(e.g., a memory stack) with dies 541 and a substrate 542 (e.g., aninterposer, wafer, or other substrate) to which the die stack 540 ismounted. The pillars 515 have an exposed portion 515B that projects awayfrom the lower surface of the substrate 542 toward thedensity-conversion connector 520. The first semiconductor deviceassembly 500A can also include one or more test pads 544 at one or moresurfaces of the substrate 542. The exposed portions 515B of the pillars515 are operatively and/or electrically connected to corresponding pads528 of the density-conversion connector 520 via one or more solder balls550 or other connection structures. For example, exposed portions 515Bpillars 515 can be at least partially embedded in the solder balls 550to establish connection between the pillars 515 and the pads 528. Thepillars 515 also have embedded portions 515A that extend at leastpartially through one or more of the substrate 542 and the die stack540. The pillars 515 are through vias, such as TSVs, that extend throughthe substrate 542 and connect to TSVs 517 that extend at least partiallythrough the die stack 540. In some embodiments, the TSVs 517 arenarrower than the through vias 515. In some embodiments, as illustratedin FIG. 10C, the pillars 515 can be in physical contact with the pads528 to reduce the distance D1 between the first semiconductor deviceassembly 500A and the substrate 522 of the density-conversion connector520. The space between the first semiconductor device assembly 500A andthe substrate 522 can be filled using known underfill techniques. Thesecond side 526 of the density-conversion connector 520 can include astandard ball-out configuration of pads 530 and/or solder balls 554(e.g., JEDEC standard and/or other standard) to electrically connect thedensity-conversion connector 520 to other semiconductor devices. In someembodiments, the solder balls 554 on the second side 526 of thedensity-conversion connector 520 can be larger than the solder balls 550on the first side 524 of the density-conversion connector 520.

Although the density-conversion connector 520 is illustrated anddescribed for use in connection with semiconductor devices havinghigh-density pillar connection, other types of semiconductor devices canalso benefit from a high-to-low or low-to-high density-conversionconnector 520. Utilization of a density-conversion connector 520 asdescribed herein can electrically couple custom-density devices (e.g.,devices designed for customer or device-specific applications) toother-density devices (e.g., devices with different custom designs orindustry-standard connection arrangements).

In some applications, it may be desirable to encapsulate or at leastpartially-encapsulate the TSV-solder connection points betweensemiconductor devices during manufacture. These methods can be usefulfor package-on-package (PoP), package-on-interposer, multi-interposer,PoP-on-interposer, interposer to multi-substrate, and/or otherapplications. For example, as illustrated in FIGS. 11A-11F and describedbelow, it may be advantageous to encapsulate solder ball connectionsbefore inserting the TSVs into the solder balls. Referring to FIG. 11A,the method can include forming solder balls 602 on pads 604 or othertypes of contacts on a substrate 606. The solder balls 602 and pads 604can be on one or more surfaces of the substrate 606 (e.g., on one, two,three, four, five, six, or more surfaces of the substrate 606). In someembodiments, the solder balls 602 may be partially or fully hardened onthe pads 604. Referring to FIG. 11B, the method can includeencapsulating the solder balls 602 and pads 604 with an encapsulant 610,such as a compression mold material or a reflow resistant.

FIG. 11C shows the method after the encapsulant 610 and solder balls 602have been ground or otherwise removed to form a top surface 612 (e.g., amating surface). In some embodiments, chemical-mechanical planarization(CMP) can be used to removes an upper portion of the encapsulant 610 andsolder balls 602 to form the top surface 612. In some embodiments, thetop surface 612 is planar. In some embodiments, nonplanar surfacefeatures can be formed on the top surface 612. For example, the solderballs 602 may be ground or otherwise removed further than thesurrounding encapsulant 610, which may result in one or moreindentations in the top surface 612 in the vicinity of the solder balls602.

FIG. 11D shows aspects of the method after an interposer or die 616having exposed or partially exposed TSVs 618 extending from a surfacethereof is aligned with the substrate 606. More specifically, the TSVs618 are at least substantially aligned with corresponding solder balls602. The method can include reflowing the solder balls 602 by, forexample, increasing the temperature of the solder balls 602 to a reflowtemperature. Referring to FIG. 11E, the exposed portions of the TSVs 618can be inserted at least partially into corresponding reflowed solderballs 602. In some embodiments, the exposed portions of the TSVs 618 areinserted into the reflowed solder balls 602 such that the TSVs 618contact the pads 604. In some applications, a space between theinterposer or die 616 in the top surface 612 of the planarizedencapsulant 610 and solder balls 602 can exist after inserting the TSVs618 into the solder balls 602.

FIG. 11F illustrates the method after the space between the top surface612 of the planarized encapsulant 610 and the interposer or die 616 hasbeen underfilled. A nonconductive film (NCF) 620 or other material canbe on the top surface 612 before inserting the TSVs 618 into thereflowed solder balls 602, or the NCF 620 can be on a surface of theinterposer or die 616 surrounding the TSVs 618 before inserting the TSVs618 into the reflowed solder balls 602. The NCF 620 can seal, insulateand protect the connections between the interposer die 616 and thesubstrate 606 in much the same manner as underfilling the space betweenthe top surface 612 and the interposer or die 616.

The methods and structures described above with respect to FIGS. 11A-11Fcan be used to manufacture many different types of semiconductor deviceassemblies. FIGS. 12A-12F illustrate some such semiconductor deviceassemblies. For example, FIG. 12A illustrates a semiconductor deviceassembly 700 having one or more semiconductor devices connected to asubstrate 702. In some embodiments, the semiconductor device assembly700 includes a first semiconductor device 704, such as a high-bandwidthmemory device (HBM) comprising one or more memory dies or othersemiconductor device. The first semiconductor device 704 can beconnected to the substrate 702 by the pillars 706 (e.g., copperpillars), solder balls, and/or other electrical connections. Thesemiconductor device assembly 700 can include a second semiconductordevice 708, such as a system on a chip (SOC) or other semiconductordevice. The second semiconductor device 708 can be connected to thesubstrate 702 via pillars, solder balls, and/or other electricalconnections.

The substrate 702 may be connected to an interposer 710 having TSVs 712that extend from the interposer 710 and/or the substrate 702. The TSVs712 can be connected to a substrate 714 using the methods describedabove with respect to FIGS. 11A-11F. For example, the TSVs 712 can beinserted into reflowed solder balls 716 which were previouslyencapsulated with an encapsulant 718 and planarized to form a topsurface. The space between the encapsulant 718 and the interposer 710 orsubstrate 702 can be underfilled or filled with an NCF 719.

FIG. 12B illustrates an embodiment of a semiconductor device assembly720 including a single or multi-ship device 722. The device 722 can beconnected to the substrate 702 via pillars 706, solder balls, and/orother electrical connections. In some embodiments, the substrate 702 iscoupled to an interposer 710 that has TSVs 712 which extend from thesubstrate 702 and/or the interposer 710. The semiconductor deviceassembly 720 can include an intermediate semiconductor device 724. Theintermediate semiconductor device 724 can include one or more single ormultichip devices 726. While electrically connecting the substrate702/interposer 710 to the intermediate semiconductor device 724 (e.g.,using the methods described above with respect to FIGS. 11A-11F), one orboth of the single or multichip devices 726 may be at least partiallyencapsulated by an encapsulant 718. In some embodiments, each of thesingle or multichip devices 726 are separately encapsulated. In someembodiments, one or more of the single or multichip devices 726 are notencapsulated. The space between the encapsulant 718 and the substrate702/interposer 710 can be filled with NCF or underfilled material 719.In some embodiments, the intermediate semiconductor device 724 isconnected to a substrate 728 via pillars 706 or solder ball connections707. Connection between the substrate 728 and the intermediatesemiconductor device 724 can be made using ball flip chip.

FIG. 12C illustrates an embodiment of a semiconductor device assembly730 having a first substrate 702 a, a second substrate 702 b, and TSVs712 that can extend from each of the first substrate 702 a and thesecond substrate 702 b. The TSVs 712 can extend in opposite directionsand/or at separate lateral positions (e.g., positions spaced apart in adirection parallel to the plane of the substrates 702 a, 702 b). Thesemiconductor device assembly 730 can further include single ormultichip devices 726 a, 726 b connected to the TSVs 712 on oppositesides of the semiconductor device assembly 730 using the methodsdescribed above with respect to FIGS. 11A-11F and FIG. 12B. One or bothof the first and second substrates 702 a, 702 b can include pads 732,testbeds, or other electrical connections formed at the substratesspaced apart from the TSVs 712. As illustrated in FIG. 12D, asemiconductor device assembly 740 can include the same components as thesemiconductor device assembly 730, wherein the first and second singleor multichip devices 726 a, 726 b are vertically aligned with each otheron opposite sides of the substrates 702 a, 702 b, and pads 732 arevertically aligned with each other on opposite sides of the substrates702 a, 702 b. In some embodiments, the semiconductor device assemblies730, 740 include an interposer 710 between the first and secondsubstrates 702 a, 702 b. In some embodiments, the first and secondsubstrates 702 a, 702 b are formed as a single unitary substrate havingTSVs extending from both sides (e.g., both a top side and bottom side ofthe substrate).

FIGS. 12E-12F illustrated embodiments of semiconductor die assemblies750, 760, respectively. Both assemblies 750, 760 include one or moresingle or multichip devices 726 connected to one or both sides of aninterposer 710 or substrate. The device 726 are connected to TSVs 712extending from the interposer 710 or substrate using the above describedmethods of FIGS. 11A-11F. The assemblies 750, 760 can include a secondsubstrate 752 connected to the interposer 710 or first substrate. Forexample, the second substrate 752 can be connected to the interposer 710(e.g., pads 756) via standard JEDEC ball out connection having one ormore solder balls 754. Other connections are also possible. The secondsubstrate 752 can be between two or more single or multichip devices726. In some embodiments, two or more of the single or multiple chipdevices 726 are encapsulated together in a single encapsulant 718 (FIG.12F). In some embodiments, each single or multiple chip device 726 isindividually encapsulated (FIG. 12E).

Any one of the semiconductor device assemblies having the featuresdescribed above (e.g., with reference to FIGS. 1-12F) can beincorporated into any of a myriad of larger and/or more complex systems,a representative example of which is system 800 shown schematically inFIG. 13. The system 800 can include a processor 802, a memory 804 (e.g.,SRAM, DRAM, flash, and/or other memory devices), input/output devices805, and/or other subsystems or components 808. The semiconductor diesand semiconductor die assemblies described above can be included in anyof the elements shown in FIG. 13. The resulting system 800 can beconfigured to perform any of a wide variety of suitable computing,processing, storage, sensing, imaging, and/or other functions.Accordingly, representative examples of the system 800 include, withoutlimitation, computers and/or other data processors, such as desktopcomputers, laptop computers, Internet appliances, hand-held devices(e.g., palm-top computers, wearable computers, cellular or mobilephones, personal digital assistants, music players, etc.), tablets,multi-processor systems, processor-based or programmable consumerelectronics, network computers, and minicomputers. Additionalrepresentative examples of the system 800 include lights, cameras,vehicles, etc. With regard to these and other examples, the system 800can be housed in a single unit or distributed over multipleinterconnected units, e.g., through a communication network. Thecomponents of the system 800 can accordingly include local and/or remotememory storage devices and any of a wide variety of suitablecomputer-readable media.

The above detailed descriptions of embodiments of the technology are notintended to be exhaustive or to limit the technology to the precise formdisclosed above. Although specific embodiments of, and examples for, thetechnology are described above for illustrative purposes, variousequivalent modifications are possible within the scope of thetechnology, as those skilled in the relevant art will recognize. Forexample, while steps are presented in a given order, alternativeembodiments may perform steps in a different order. Moreover, thevarious embodiments described herein may also be combined to providefurther embodiments. Reference herein to “some embodiments,” “anembodiment,” or similar formulations means that a particular feature,structure, operation, or characteristic described in connection with theembodiment can be included in at least one embodiment of the presenttechnology. Thus, the appearances of such phrases or formulations hereinare not necessarily all referring to the same embodiment.

Certain aspects of the present technology may take the form ofcomputer-executable instructions, including routines executed by acontroller or other data processor. In some embodiments, a controller orother data processor is specifically programmed, configured, and/orconstructed to perform one or more of these computer-executableinstructions. Furthermore, some aspects of the present technology maytake the form of data (e.g., non-transitory data) stored or distributedon computer-readable media, including magnetic or optically readableand/or removable computer discs as well as media distributedelectronically over networks. Accordingly, data structures andtransmissions of data particular to aspects of the present technologyare encompassed within the scope of the present technology. The presenttechnology also encompasses methods of both programmingcomputer-readable media to perform particular steps and executing thesteps.

Moreover, unless the word “or” is expressly limited to mean only asingle item exclusive from the other items in reference to a list of twoor more items, then the use of “or” in such a list is to be interpretedas including (a) any single item in the list, (b) all of the items inthe list, or (c) any combination of the items in the list. Where thecontext permits, singular or plural terms may also include the plural orsingular term, respectively. Additionally, the term “comprising” is usedthroughout to mean including at least the recited feature(s) such thatany greater number of the same feature and/or additional types of otherfeatures are not precluded. Further, while advantages associated withcertain embodiments of the technology have been described in the contextof those embodiments, other embodiments may also exhibit suchadvantages, and not all embodiments need necessarily exhibit suchadvantages to fall within the scope of the technology. Accordingly, thedisclosure and associated technology can encompass other embodiments notexpressly shown or described herein.

What is claimed is:
 1. A method of coupling a first semiconductor deviceto a second semiconductor device, the method comprising: encapsulatingsolder balls on a first surface of a first substrate of the firstsemiconductor device with an encapsulant material; removing a portion ofthe encapsulant material and a portion the solder balls to form a matingsurface; reflowing the solder balls; and inserting exposed conductivepillars of the second semiconductor device into the reflowed solderballs.
 2. The method of claim 1, wherein the conductive pillars extendfrom a first surface of a substrate of the second semiconductor deviceand the method further comprises filling a space between the matingsurface and the first surface of the substrate of the secondsemiconductor device.
 3. The method of claim 1, further comprisingcontacting the electrical contacts on the first surface of the firstsubstrates of the first semiconductor device with the conductivepillars.
 4. The method of claim 1, wherein the second semiconductordevice comprises a substrate having a first surface and a second surfaceopposite the first surface, wherein the conductive pillars extend fromthe first surface of the second semiconductor devices, and wherein athird semiconductor device is connected to the second surface of thesecond semiconductor device.
 5. The method of claim 1, furthercomprising removing material from the second semiconductor device toexpose the exposed portions of the conductive pillars.
 6. The method ofclaim 1, wherein removing a portion of the encapsulant material and aportion the solder balls comprises one or more of grinding theencapsulant and the solder balls, using chemical-mechanicalplanarization, etching, and/or ablating.
 7. The method of claim 2,wherein filling the space between the mating surface and the firstsurface the substrate of the semiconductor device comprises positioningnon-conductive film material between the mating surface and the firstsurface of the substrate of the second semiconductor device.
 8. Themethod of claim 2, wherein filling the space between the mating surfaceand the first surface of the substrate of the semiconductor devicecomprises underfilling the space between the mating surface and thefirst surface of the substrate of the second semiconductor device. 9.The method of claim 5, wherein the conductive pillars arethrough-silicon vias.
 10. A method of manufacturing a semiconductordevice assembly, the method comprising: encapsulating solder balls onthe first set of contacts of a first substrate with a first encapsulant;removing a portion of the first encapsulant to expose a portion of thesolder balls on the first set of contacts; reflowing the solder balls onthe first set of contacts after removing the portion of the firstencapsulant; and inserting a first set of exposed conductive pillarsextending from a second substrate into the reflowed solder balls on thefirst set of contacts.
 11. The method of claim 10, further comprising:forming solder balls on a second set of contacts; encapsulating thesolder balls on the second set of contacts with a second encapsulant;removing a portion of the second encapsulant to expose a portion of atleast one of the solder balls on the second set of contacts; reflowingthe solder balls on the second set of contacts after removing theportion of the second encapsulant; inserting a second set of exposedconductive pillars extending from the second substrate into the reflowedsolder balls on the second set of contacts.
 12. The method of claim 10,wherein encapsulating the solder balls on the first set of contactscomprises encapsulating at least a portion of the first substrate. 13.The method of claim 11, wherein the first set of pillars extend from thesecond substrate in a first direction, and wherein the second set ofpillars extend from the second substrate in a second direction oppositethe first direction.
 14. The method of claim 11, wherein the second setof contacts are formed on a third substrate.
 15. The method of claim 11,wherein the second set of contacts are formed on the first substrate.16. The method of claim 11, wherein encapsulating the solder balls onthe second set of contacts comprises encapsulating at least a portion ofthe first substrate.
 17. The method of claim 12, wherein encapsulatingthe solder balls on the second set of contacts comprises encapsulatingat least a portion of a third substrate.
 18. The method of claim 17,wherein first encapsulant is separate from the second encapsulant. 19.The method of claim 17, wherein the first encapsulant and the secondencapsulant are two portions of a same encapsulant encapsulating boththe first substrate and the second substrate.
 20. A method ofmanufacturing a semiconductor assembly, the method comprising: providinga first substrate having a first set of solder balls encapsulated in afirst encapsulant on a first side of the first substrate; removing aportion of the first encapsulant to partially expose the first set ofsolder balls; increasing the temperature of the exposed first set ofsolder balls to a reflow temperature; and inserting a first set ofexposed conductive pillars into the reflowed first set of solder balls.21. The method of claim 20, wherein the first set of exposed conductivepillars comprise through-silicon vias extending from a second substrate.22. The method of claim 20, further comprising: providing a secondsubstrate having a second set of solder balls encapsulated in a secondencapsulant on a first side of the second substrate; removing a portionof the second encapsulant to partially expose the second set of solderballs; reflowing the second set of solder balls; and inserting a secondset of exposed conductive pillars into the reflowed second set of solderballs.
 23. The method of claim 20, further comprising contacting pads onthe first side of the first substrate with the first set of exposedconductive pillars.
 24. The method of claim 22, wherein the first andsecond encapsulants are two portions of an overall third encapsulantencapsulating the first and second sets of solder balls.
 25. The methodof claim 22, wherein the first encapsulant is separate from the secondencapsulant.
 26. The method of claim 22, wherein the first and secondsets of exposed conductive pillars extend from a third substrate. 27.The method of claim 22, further comprising: providing a third substratehaving a third set of solder balls encapsulated in a third encapsulanton a first side of the third substrate; removing a portion of the thirdencapsulant to partially expose the third set of solder balls; reflowingthe third set of solder balls; and inserting a third set of exposedconductive pillars into the reflowed third set of solder balls.
 28. Themethod of claim 27, wherein the first set of exposed conductive pillars,the second set of exposed conductive pillars, and the third set ofexposed conductive pillars all extend from a fourth substrate.
 29. Themethod of claim 28, wherein the first set of exposed conductive pillarsextend in a first direction from the fourth substrate, the second set ofexposed conductive pillars extend in a second direction from the fourthsubstrate, the third set of exposed conductive pillars extend in a thirddirection from the fourth substrate, and wherein the first direction isdifferent from the second direction and/or the third direction.